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Updated: Jul 19, 2026
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Using SecM Arrest Sequence as a Tool to Isolate Ribosome Bound Polypeptides
Published on: June 19, 2012
[A regulatory protein isolated from cattle milk].
Prikladnaia Biokhimiia I Mikrobiologiia
|October 28, 2006
Summary
A novel regulatory protein active at ultralow doses was found in cow's milk. This protein, identified as a low-molecular-weight serum glycoprotein, is present in whole milk but not in dry or infant formulas.
Area of Science:
- Biochemistry
- Molecular Biology
- Dairy Science
Context:
- Cow's milk contains numerous bioactive compounds.
- Regulatory proteins play crucial roles in biological systems.
- Understanding milk composition is vital for nutrition and health.
Purpose:
- To identify and characterize a novel regulatory protein in cow's milk.
- To determine the protein's physicochemical and structural properties.
- To ascertain the protein's presence and activity in different milk forms.
Summary:
- A regulatory protein with biological activity at ultralow doses was identified in cow's milk.
- The protein exhibits an isoelectric point of 4.48-5.59, molecular weight <10 kDa, and predominantly antiparallel beta-structures.
- It is located extracellularly in mammary duct epithelium, active in whole milk, but absent in dry milk and infant formula.
- The findings suggest this protein is identical to low-molecular-weight serum glycoprotein.
Impact:
- Identifies a new bioactive component in milk with potential therapeutic or nutritional applications.
- Provides insights into the structural and functional characteristics of milk proteins.
- Highlights the importance of processing methods on the preservation of bioactive milk components.
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